1. Field of the invention
The present invention relates to an electrophotographic photoreceptor comprising specific butadiene compounds as an essential component. The present invention also relates to an electrophotographic photoreceptor comprising an electroconductive support on which a photosensitive layer is placed, which layer contains specific butadiene compounds as an essential component. The present invention also relates to the electrophotographic photoreceptor which is desirably used in image forming apparatus such as laser printers and LED printers.
2. Prior Art
Considerable studies on an electrophotographic photoreceptor comprising organic photoconductive compounds have been made in recent years in view of the fact that these electrophotographic photoreceptors give a superior performance, e.g., light weight, high surface smoothness, low toxicity, easy productivity and low prices, compared with those containing inorganic photoconductive compounds. As the electrophotographic photoreceptor comprising organic photoconductive compounds, a so-called functional separation type electrophotographic photoreceptor having a structure which is functionally separated into a charge generating layer and a charge transfer layer has attracted considerable attention.
Various materials have been proposed for addition to the charge generating layer or in the charge transfer layer.
Among these various materials, charge transfer materials having various properties have been exploited and proposed (for instance, U.S. Pat. No. 3,791,826).
Examples of the charge transfer materials include 1,1,4,4-tetraphenylbutadiene derivatives having at least one substituted amino group disclosed in Japanese Patent Publication (JP-B) No. H5-19701,1-(p-aminophenyl)-1,4,4-triphenylbutadiene derivatives or 1,1-bis(p-aminophenyl)-4,4-diphenylbutadiene derivatives disclosed in JP-B No. H7-21646.
JP-B No. H7-27244 proposes an electrophotographic photoreceptor comprising these tetraphenylbutadiene derivatives as the charge transfer materials and oxotitanium phthalocyanine as the charge generating material. Further, Japanese Patent Application Laid-Open (JP-A) No. H5-134428 proposes an electrophotographic photoreceptor comprising tetraphenylbutadiene derivative as the charge transfer material and a specific polycarbonate resin as a polymer binder.
However, the characteristics of these electrophotographic photoreceptors comprising these tetraphenylbutadiene derivatives as the charge transfer materials are unsatisfactory.